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San Mateo County, California WARN notices

San Mateo County, California has 581 non-cancelled imported WARN notices reporting 46,943 workers affected. 6 notices have future effective dates. These totals cover imported records only.

What the official notice history shows

During the last 365 days, this imported archive contains 47 eligible official filings for San Mateo County, California, reporting 6,121 affected workers. 0 worker counts are unavailable. The newest official notice date is Sep 14, 2026.

580 non-cancelled direct government records and 1 attributed secondary records appear in the full archive. Recent official event types: layoff, closure. These figures describe notices, not unique people or completed layoffs. Grouped company names do not establish ownership.

Compare original weekly and monthly official-data reports → · How dates, names and counts are interpreted

581Non-cancelled notices
46,943Reported workers
6Future effective dates
Coverage is limited to connected sources and imported date ranges. 0 notices have unavailable worker counts. Company groups match normalized names; aliases below preserve exact employer names from filings. Methodology →

Notice history by year

202638 notices · 5,521 reported workers
202562 notices · 3,309 reported workers
202448 notices · 3,865 reported workers
2023129 notices · 5,388 reported workers
202244 notices · 4,115 reported workers
202142 notices · 2,917 reported workers
2020170 notices · 18,271 reported workers
201923 notices · 1,595 reported workers
201817 notices · 1,372 reported workers
20177 notices · 515 reported workers
20161 notices · 75 reported workers
Oracle America →California →Redwood City →LeeMAH Electronics →Brisbane →Arsenal Biosciences →South San Francisco →Cellares →FLYING FOOD GROUP →Burlingame →Visa →Foster City →Yerba Mate Co., LLC - South San Francisco →Flagship Facilities Services →Genentech →

Filings and attributed reports

Company / locationWorkersEffective dateNotice dateType / source
Sanitation SpecialistsSan Mateo, CA15May 22, 2026Mar 12, 2026closureSource ↗
Heritage Bank of Commerce (Mateo)Suite 150 Mateo, CA5Apr 17, 2026Feb 27, 2026layoffSource ↗
C3.aiSan Mateo, CA71Apr 26, 2026Feb 23, 2026layoffSource ↗
Meta Platforms, Inc. - 180 JeffersonSan Mateo, CA2Mar 20, 2026Feb 2, 2026layoffSource ↗
Meta Platforms, Inc. - 220 JeffersonSan Mateo, CA2Mar 20, 2026Feb 2, 2026layoffSource ↗
Meta Platforms, Inc. - 1 HackerSan Mateo, CA6Mar 20, 2026Feb 2, 2026layoffSource ↗
Meta Platforms, Inc. - 190 JeffersonSan Mateo, CA1Mar 20, 2026Feb 2, 2026layoffSource ↗
Meta Platforms, Inc. - 305 ConstitutionSan Mateo, CA39Mar 20, 2026Feb 2, 2026layoffSource ↗
Chan Zuckerberg InitiativeSan Mateo, CA38Mar 30, 2026Jan 29, 2026layoffSource ↗
Chan Zuckerberg Initiative, LLC - RemoteSan Mateo, CA32Mar 30, 2026Jan 29, 2026layoffSource ↗
ResoneticsSan Mateo, CA61Apr 21, 2026Jan 20, 2026closureSource ↗
Meta PlatformsSan Mateo, CA219Mar 20, 2026Jan 16, 2026layoffSource ↗
InformaticaSan Mateo, CA35Feb 28, 2026Jan 12, 2026layoffSource ↗
Transdev ServicesSan Mateo, CA77Dec 31, 2025Oct 30, 2025closureSource ↗
GenentechSan Mateo, CA118Nov 28, 2025Oct 24, 2025layoffSource ↗
Dairyland ProduceSan Mateo, CA22Dec 24, 2025Oct 23, 2025layoffSource ↗
Meta PlatformsSan Mateo, CA3Dec 22, 2025Oct 22, 2025layoffSource ↗
Meta PlatformsSan Mateo, CA21Dec 22, 2025Oct 22, 2025layoffSource ↗
Meta PlatformsSan Mateo, CA1Dec 22, 2025Oct 22, 2025layoffSource ↗
Meta PlatformsSan Mateo, CA22Dec 22, 2025Oct 22, 2025layoffSource ↗
Meta PlatformsSan Mateo, CA261Dec 22, 2025Oct 22, 2025layoffSource ↗
AlectorSuite 600 South San Francisco, CA75Dec 22, 2025Oct 21, 2025layoffSource ↗
Kaiser Foundation Hospitals (1100)San Mateo, CA20Sep 17, 2025Oct 6, 2025layoffSource ↗
Oracle AmericaSan Mateo, CA4Nov 10, 2025Oct 1, 2025layoffSource ↗
Sutro BiopharmaSan Mateo, CA45Sep 30, 2025Sep 29, 2025layoffSource ↗

581 notices · Source check Oct 9, 2026

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